Moistening mechanism for offset duplicating machines



Oct. 25, 1955 v. MILENKOVIC MOISTENING MECHANISM FOR OFFSET DUPLICATING MACHINES Hll 3 Sheets-Sheet 1 1mm mmH.

Filed Jan. 1'7, 1952 Oct. 25, 1955 v. MILENKOVIC 2,721,515

MOISTENING MECHANISM FOR OFFSET DUPLICATING MACHINES 3 Sheets-Sheet 2 Filed Jan. 17, 1952 'INVENTOR. ye Z /raflden/zouw, M

Oct. 25, 1955 v. MILENKOVIC 2,721,515

MOISTENING MECHANISM FOR OFFSET DUPLICATING MACHINES Filed Jan. 17, 1952 3 Sheets-Sheet 3 INVENTOR.

United States Patent MOISTENING MECHANISM FOR OFFSET DUPLICATING MACHINES Veljko Milenkovic, Chicago, 11]., assignor to Ditto, incorporated, Chicago, 111., a corporation of West Virgmra Application January 17, 1952, Serial No. 266,940

11 Claims. (Cl. 101148) This invention relates to a plate dampening device particularly adapted for use in duplicating machines of the offset, lithographic type.

It is an object of this invention to provide a planegraphic plate dampening device which permits the ready selection of any desired rate of application of the moistening liquid and which also permits an immediate temporary adjustment to the maximum amount, Whenever desired.

Another object of the invention is to provide such a moistener which has a continuously rotating moisture fountain roll, and a train of rolls adapted to cooperate in such a fashion therewith as to produce a very even and accurately controlled supply of moisture to the plate.

Still another object is to provide a variable means for directing moisture to the plate which is adjustable, not only as to the rate of moisture delivery, but is adjustable locally so that the width of the normal moisture pattern on the train of rollers associated with the moisture fountain roll may be selected in accordance with the width of the sheet being printed.

The moistening mechanism which is the subject matter of this application is particularly adapted for use with an offset, lithographic, duplicating machine such as that disclosed in the copending application, Serial No. 154,009, filed April 5, 1950, in the name of Herbert F. Bruns. The drawings accompanying this application are illustrative of portions of a machine of that construction, but it is obvious that the machine may have any desired form as long as it is so constructed that the lithographic plate can be periodically moved and a moisture form roll can be moved into rolling contact therewith.

Further objects and advantages of this invention will become evident as the description proceeds and from an examination of the accompanying drawings which illustrate one embodiment of the invention and in which similar numerals refer to similar parts throughout the several views.

In the drawings:

Figure 1 is a view in elevation and partly in vertical section of one form of moistening mechanism incorporating the invention which is the subject matter of this application;

Figure 2 is a side view in elevation and partly in vertical section, the view being taken along the line 22 of Figure Figure 3 is a somewhat diagrammatic elevational view of a moisture fountain and its associated train of rolls included to further clarify the organization of the moistening mechanism;

Figure 4 is an enlarged fragmentary view in elevation and partly in vertical section of a portion of the mounting mechanism for the ductor roll, shown in Figure 2;

Figure 5 is a fragmentary side view in elevation of a portion of the mechanism shown in Figure 1, showing the means for selecting the rate of application of moisture to the plate, together with the booster which is adapted to cooperate therewith;

2,721,515 Patented Oct. 25, 1955 Figure 6 is a fragmentary view in elevation of a portion of the means for selecting the rate of application of moisture to the plate, with some of the parts thereof removed;

Figure 7 is a view in elevation and partly in vertical section of the moisture fountain roll shown in Figures 1, 2 and 3, together with the mounting therefor;

Figure 8 is a view in vertical section of a portion of the mounting means for the ductor roll of the moistening mechanism;

Figure 9 is an end view in elevation of the fountain roll shown in Figure 7, the view being taken toward the left as shown in that figure;

Figure 10 is a view in vertical section of a clutch mechanism at one end of the moisture fountain roll, the view being taken along the line 1010 of Figure 7.

Figure 11 is a diagrammatic representation of a portion of the surface of the moisture form roll.

Referring now to Figures 1, 2 and 3, the moistening mechanism indicated generally by the numeral 12 may be disposed as best shown in Figure 2 in close association with the cylinder 14 of the duplicating machine, which cylinder is normally provided with a plate carrying segment. The moistener is provided with a train of rolls, best shown in Figure 3, including the moisture fountain roll 16, a ductor roll 18, a rider or idler roll 20, and a moisture form roll 22. A moisture fountain 24 is provided with which the moisture fountain roll 16 is so associated that it is normally adapted to have its lower portion normally submerged in a moistening liquid 26 contained in the fountain 24. The fountain 24 may be supported on the pins 28 and 30 (Figure 2), which pins in turn are supported by the side plate 32 (Figure 1), similar components also being provided in association with the side plate 34.

The moisture fountain roll 16, as best shown in Figures 1 and 7, is rotatably mounted between the side plates 32 and 34 and is rotated by the gear 36 which is in turn driven by suitable Gilmer timing belt which, in turn, may derive its motion from an electric motor (not shown) in a manner such that as that shown in the above identified copending application. The gear 36 may be secured to the shaft 38 by a set screw 40, the shaft being journalled in the opening 42 in the side plate 34, which opening is provided with a suitable bearing 44. The inner extremity of the shaft 38 has a collar 46 slidably mounted thereon, which collar is normally urged in a direction away from the side plate 34 by a spring 48 and is prevented from rotating by a pin 50 on the shaft 38, which pin is adapted to be received in the axial slot 52 in the collar 46. The outer end of the collar 46 is provided with a diametrically disposed slot 54 which is adapted to snugly receive the tongue 56 (Figure 9) projecting from the collar 57, while the outer extremity 58 of the shaft 60 of the moisture fountain roll 16 is adapted to be received within the bore 62 of the collar 46. A pin 64 is also provided on the outer extremity 58 of the shaft 60, which pin is adapted to also be received in the slot 52 in the collar 46.

The opposite end of the shaft 60 of the moisture f011ntain roll 16 is provided with a collar 66, the outer face of which has a tongue 68 projecting therefrom which is adapted to be received in the clutch 70, the inner end of which has the grooves 72 formed therein disposed in the form of a cross, so that the shaft 60 may be disposed in any one of four different angular positions relative to the clutch 70, as desired, the four positions being 90 apart.

The clutch is secured to the shaft 74 by the set screw 76 so that the angular relation of the clutch to the shaft may be adjusted as desired. The reduced portion 78 of the bore 80 in the clutch 70 at its inner extremity is adapted to receive the outer extremity 82 of the shaft 60. The shaft 74 is journalled in the opening .84 in the side plate 32, which opening also extends 3; through the boss 86 formed on the outer surface of the side plate 32, the opening 84 being provided with a suitable bearing 88.

This construction also enables themoisture fountain roll 16 to be removed or inserted by applyingforce to the roll in an axial direction-toward the side plate 34 and sliding the collar 46 on the shaft 38 toward the side plate 34. The outer extremity of the opposite endsofthe shaft 69 and the tongue 68 may be then moved. into or out of association with the clutch 79, as described. above.

The surface of the moisture fountain roll is divided into four quadrants a, b, c and d, as best shown in Figures 7 and 9. Quadrant a (shown only in Figure 9) has a full cylindrical surface throughout its entire width while quadrants b, c and d have a full cylindricalsurface only for a very narrow portion thereof, namely, b., c andidf, respectively. The full cylindrical surface d is actually integral with the full cylindrical surface of quadranta, as best shown in Figure 9. Each of the quadrants b, c and d therefore has a relieved portion bb, cc and dd. at each extremity thereof adjacent the ends of the roll 16. The remaining cylindrical portions of the quadrants a, b, c and d preferably diminish in length, in that order, so that conversely the relieved portions bb, cc and dd increase in length, in that order.

The shafts 38 and 74 to which the moisture fountain roll is normally keyed are each journalled in identical brackets 99 and 92, respectively, the exact form of these brackets being shown in Figure 2. Each bracket at its lower extremity is provided with an opening94 having a suitable bearing 96 therein, as best shown in Figure 7. The opposite end of the brackets 90 and 92 are provided with a slot 98 which is adapted to receive the greatly reduced outer extremities of the shaft 1190 of the moisture form roll 22. This end of each of the brackets 90 and 92 is also provided with a pin 102 projecting therefrom and one end of a spring 104 is secured to the pin 102 with the other end of the spring being secured to the side plate associated with the bracket. The spring 104 is disposed so as to urge its associated bracket toward the cylinder 14. Thus when the moisture form roll is mounted in the brackets and 92, it isnormally urged in a direction toward the cylinder 14.

The shaft 1% of the moisture form roll has the cam follower rollers 106 and 108 mounted thereon at each of its opposite extremities. These cam followers are in turn adapted to make rolling contact with ring cams mounted at opposite ends of the cylinder 14, such as the cam 11!! shown in Figure 2. The configuration of these cams is such that the moisture form roll is moved out of rolling contact with the cylinder at the trailing end of the plate segment thereof and is moved into rolling contact with the cylinder at the. leading end of the plate segment.

A second slot 114 is formed'in the brackets 90'and92 in spaced relation to the slot 98 and is adapted to receive in supported relation the bearing 116 in which the rider roll shaft 118 is journalled. A spring member 120 has one end 122 mounted on the bracket 90 and extends upwardly into association with the slot 114 in such fashion that the bearing 116 and the shaft 118 are normally urged by the spring 120 to move in a direction such that the idler roll 20 is brought into rolling contact with themoisture form roll 22.

By such an arrangement the moisture form roll 22 and the idler roll 20 may both be moved from their normal position in the moisture mechanism, as shown in Figures 2 and 3, by releasing the spring 1fi4 from pin 102' on the bracket 90, and allowing the bracket 90 to pivot in a counterclockwise direction as viewed in Figure 2.

It will be understood that the above description, although directed primarily to bracket 90, also is equally applicable to bracket 92 and the similar elements associated therewith.

A.second:boss 126 is=provide OnLthe side plate 32- 4: above. the boss 86 and has journalled therein a. shaft 128. This shaft 128 in turn has secured to the inner end thereof an arm 130, which arm is resiliently secured to the upper end of the arm 132, the opposite end of this arm being pivotally secured, in turn, to the arm 134 carried by the shaft 136, as best shown in Figure 8. The shaft 136 is disposed within the tube 138 which tube is pivotally mounted to the shaft 136 at substantially the'midpoint thereof by the pin 140, so that the tube 138 may pivot slightly about the pin 140 in-a plane substantiallyperpendicularthereto. Theouter extremities of thetube 138 have a slot 141 formed therein disposed in that plane, which slot is adapted to receive-the pin 142 on the shaft 136 disposed at right angles to the pin 140.

The outer extremities of the shaft 136 are journalled in the bearings 143 which are in turn mounted in the openings 144 in the brackets and 92. The outer extremities of'the tube 138 have the forked arms- 146. se-

cured theretoin' which the extremities of the ductor roll shaft 148 are adapted to be removably'held in suitable bearing members. 151 Because of the manner in which the. tube: 138* is mounted on the shaft 136, as describedabove, the-ductor roll may pivot'slightly about the pin and therefore be self-aligning with respect to rollsv 16 and 20.

The arm 130 on the shaft 128 has a pin 152 projecting.

therefrom to which the upper end" of the spring 154 is adapted to. be secured. The other end of thespring 154* maybe secured tothe hanger member 28'which supports the moisture fountain 24. Thus thespring 154 is adapted to normally urge the arm 130 to pivot in a counterclockwise direction, as viewed in Figure. 2, together with the shaft 128. This means that the. arm 132, inturn, is normally urged to move longitudinally in a direction toward. the'moisture fountain roll 16 which causes the arm member 134 and the. shaft 136 to rotate. in a counterclockwise direction. The tube 138, to which the forked arm members 132 are secured, is thus causedto rotate.

in a counterclockwise direction, asviewed in Figure. 2, since it is secured to the shaft 136.by the pin 140, as previously described. Rotation of'the tube 138 in this manner will cause the forked arms 146 to pivot in the same directionabout the3shaft-136'so that the'ductor roll 18 ismoved toward the moisture fountain roll 16'; until it comes into contact therewith.

The arm 132. is provided with a reduced upper end 156,

asbestsh'own'in Figure 4, and has a collar member 158' slidably" mounted thereon. A-spring member 169is disposed between the collar member 153 and'a washer 162, secured to the outer extremity of the reducediportion 156, so as to normally urge the collar member 158 into abutting relation with the flange 163 on the-.upper endof the arm 132; The collar 158' issecured to the: outer ex-" trernity of'the arm 13% so that downward movement of the arm 130 normally is imparted directly to the arm 132' at the flange 163. When the arm 130 is-pivoted in a clockwise'direction (as viewedin Figure 2), as will be subsequentlyexplained, the. arm1132 willbemoved upwardly-by a compression force being applied to thespring by the collar 158.

It will be seen by the above arrangement that rotation of the shaft 123will in turn causeiamovement of the ductor roll 18. To provide for the desired adjustable re-. ciprocal'motion of the ductor rolllsbetween the moisture fountain roll11'6zand the idler roll 20, the outer extremity'of the shaft 12$:has one end. of. an arm 164 clamped thereto by the bolt 166. The oppositeend of the arm 164 may have the cam follower roller 168 1-0- tatably mounted thereon and a second cam'follower roller 170 of smaller diameter also rotatably mounted thereon, immediately. adjacent to the'roller 168,- both rollers being held in this position by the bolt 172;

The: shaft 74, which has beenwpreviously'described as being *journallettimther bearing member 88 in'the open' ing 84 in the boss 86 on the side plate :32, extendsoub wardly from the boss 86 and has secured thereto the cam member 174 by the pin 176, as best shown in Figure l. The cam follower roller 168 is so disposed as to cooper ate with this cam 174. A second cam 178 is rotatably mounted on the base 180 of the collar or hub 182 which may be formed integrally with the cam 174. The cam follower roller 170 is so disposed as to cooperate with this second cam 178. The outer extremity 184 of the collar or hub 182 has a sun gear 186 formed thereon, while the second cam 178 has an outwardly projecting peripheral flange 188 formed thereon having an internal ring gear 190 formed thereon.

The shaft 74 is provided with a reduced outer extremity 192 which has the elongated pinion 194 mounted to rotate freely thereon in close association with the collar 182. The pinion 194 may be held in place by the lock nuts 196 threaded on the outer end of the reduced outer extremity 192 of the shaft 74 with the antifriction bearing 197 disposed between the nuts 196 and the outer end of the pinion 194. The outer end of the pinion 194 has a control knob 198 secured thereto by the set screw 199 and the knob has secured thereto a pointer arm 200 which is adapted to cooperate with the serrated edge 201 on the spider 204 which member is rotatably mounted on the central collar portion 202 of the pinion 194.

The inner face 206 of the spider 204 has a recess 208 formed therein, the inner wall of which is of circular form, as best shown in Figure 5. A gear segment 210 is pivotally mounted at its center of rotation on the pin 212, which pin is secured to the inner face 214 of the recess 208. The toothed edge of the gear segment 210 has a radius of curvature substantially equal to the radius of curvature of the inner wall of the recess 208 and is disposed so as to mesh with the teeth 216 on the inner end of the pinion 194. A cover plate 218 may be disposed between the inner surface 206 of the spider 204 and the outer extremity 184 of the collar 182. A pair of planetary gears 220 and 222 are rotatably mounted on pins 224, which pins extend through the cover plate 218 into secured relation with the spider 204. These gears are disposed so as to mesh with both the sun gear 186 and the internal ring gear 190 on the cams 168 and 170, respectively.

The gear segment 210 is provided with an arm 226 which extends outwardly from the pivot pin 212 in a direction diametrically opposite to the toothed portion of the segment, and is pivotally secured by the pin 228 to a bracket 230 carried by the shaft 232. This shaft is normally held in a fixed position by the spring 234, shown in Figure 5, slidably mounted in the brackets 236 and 238 secured to the side wall 32. The shaft 232 also has secured thereto, intermediate its two ends, a bracket 240, which bracket is also secured to one end of the bellows 242. The opposite end of the bellows 242 is secured to the bracket 236. As shown in Figure 5, when the bellows is in its normal, unexpanded condition, the spring 234 acts on the washer 244 pinned to the end 246 of the shaft 232 to maintain the shaft 232 in a retracted position, so that the pin 248 at the opposite end 250 of the shaft 232 is held in abutment with the bracket 238. Since the shaft 232 is freely slidable in the brackets 238 and 236, expansion of the bellows 242 will cause the spring 234 to be compressed and the shaft 232 will move to the right, as viewed in Figure 5. Such movement of the shaft 232 will in turn cause the bracket 230 carried thereby to also move carrying with it the arm 226 of the gear segment 210.

It is often desirable to have means provided for permitting the ductor roll 18 to be moved into rolling contact with the idler roll 20 but preventing it from moving into contact with the fountain roll, regardless of the setting of the control mechanism and the knob 198. To accomplish this in the present device the electromagnetically controlled latch 252 is provided which is pivotally mounted on a pin 254 on the side plate 32 so that the lower 6 end 256 of the latch 252 will normally be moved into contact with the stop 258 by the spring 260. The stop 258 is secured to the arm 164 above the shaft 128 and when in the position shown in dotted lines in Figure 5 will prevent the arm 164 from pivoting about the shaft 128 in a counter-clockwise direction. The electromagnet 262 is disposed on the bracket 262 which is secured to the side plate 32 and is adapted to draw the arm of the latch 252 out of association with the stop 258 when energized. When the electromagnet 262 is deenergized the spring 260 secured to the upper end 266 of the latch 252 and the bracket 264, will normally cause the latch to rotate about the pin 254 and bring the lower end 256 of the latch 252 into locking relation with the stop 258 when the arm 164 is moved in a clockwise direction about the shaft 128 by the action of the rise on the cam 174. A stop push button control may likewise control the electromagnet 262, which button preferably may be disposed so that it can be conveniently operated by the operator, be automatically operated, or in conjunction with another adjustment.

Operation As previously stated, the moisture fountain roll 16 is adapted to be normally rotated by the driven gear 36 on the shaft 38 which is rotated in synchronism with the cylinder 14. Rotation of the roll 16 in turn causes the shaft 74 to rotate which has the cam 174 secured thereto, as previously mentioned. As shown in Figures 5 and 6, the configuration of the cam 174 is such that the cam follower 168 and the arm 164 will be caused to move in a counter-clockwise direction during a substantial portion of each revolution of the cam 174. As the cam 174 rotates, so does the sun gear 186 which, as previously mentioned, is disposed in meshing relation with the planetary gears 220 carried by the spider 204. Since the spider 204 is normally held against rotation by the pin 228 pivotally securing the arm 226 of the gear segment to the normally stationary bracket 230, rotation of the sun gear 186 will cause the planetary gears 220 and 222 to rotate. Rotation of these gears will in turn cause the cam 178, having the internal ring gear 190 formed thereon meshing with the planetary gears 220 and 222, to rotate in a direction opposite to the direction of rotation of the cam 174.

As shown in Figures 5 and 6, the cam 178 has a configuration such that when the cam follower roller 168 enters the dwell on the cam 174, the cam follower roller 170 will be moved into rolling contact with the cam 178. The various elements associated with the ductor roll 18 may be so designed and positioned as to cause the ductor roll to be in rolling contact with the idler roll 20 when the cam follower roller 168 is on the rise of the cam 174. Likewise these elements may be so designed and disposed that the ductor roll is in contact with the moisture fountain roll 16 when the cam follower roller 170 is in rolling contact with the dwell on the second cam 178. Similarly the ductor roll 18 is adapted to be disposed in a position out of contact with both the moisture fountain roll 16 and the idler roll 20, when the cam follower roller 170 is in rolling contact with the rise of the cam 178.

This means that in the normal cycle of operation the ductor roll 18 will be held in contact with the rider roll 20 a fixed period of time during a specific portion of the cycle of operation. This is true because the cam 174 is rotating in synchronism with the moisture fountain roll 16 which is in turn rotating in synchronism with the cylinder 14. Assuming that the cam 178 is angularly adjusted relative to cam 174 so that the dwell of the cam 178 is adjacent the cam follower 170 during the entire period of time in which the dwell of the cam 174 is adjacent the cam follower 168, the ductor roll 18 would than also be within contact with the moisture fountain roll 16 a fixed period of time during each cycle of operation. If the angular disposition of the cam 178 relative to the cam 174 is modified, however, so that when the cam follower 168"initia1ly enters the dwell in the cam 174, the cam follower 170 comes into 'contact with the rise on cam 178,v

the ductor roll will be held out ofcontact with both the rider roll and the moisture fountain roll until the follower roll i170 enters thedwell on the cam 1'78.

This'in turn means that the period'of time during each cycle in which the ductor roll is in rolling contact with the moisture fountain roll, may be varied as desired by varying the amount of timeithat the cam follower 170 is in contact.with the rise. on the cam 178. The cam 174 in the embodiment illustrated in the drawings is adapted to rotate in aclockwise direction, as viewed in Figures 5 and 6; Likewise the cam 178 is designed to rotate in a counter-clockwisedirectionas viewedin these two figures. This meansthat the follower 168Iwill enter the dwell on the cam 174'at the point 268. If by the time point 270 passes under the follower roller 168, the rise 272 on the cam 178has passed beneath the follower 170 the ductor roll will move immediately from contact with the rider roll'to' contact with the fountain roll. However, if a portion of the rise 272 on the cam 178 has not yet passed under the follower 170, this follower will enter the dwell on: the cam178substantially at the point 27 0. The distance between the point at which the follower 170 first contacts the rise 272 on the cam 178 and the pointy 270 on that cam, determines how long the ductor roll will be out of contact with both theidler roll and the fountain roll. By varying the relative. radial position of the cam 1'78. and the cam 174, this period of time can thus be adjusted as desired.

'lthough the adjustment of the relative angular disposition of the two cams 174 and 178 could be accomplished by direct adjustment of the radial position of the spider 204, it is desirable to provide a control means which will now give a much finer adjustment than would the direct movement of the spider 204. To accomplish this, as previously described, the pinion 194 is mounted to rotate freely on the shaft 12 which is an extension of the shaft'74. The spider 204 is in turn rotatably mounted'on thecentral portion of the pinion in the form of the collar 202. The gear segment 210is-pivotally secured to the spider in a recess provided for that purpose and the teeth of the. gear segment are disposed in meshing relation with the teeth 216 of the pinion 194.

Rotation of the knob 198 which is secured to the opposite end of the pinion 194 causesthe pinion inturn: to rotate. Rotation of the pinion would normally causethe gear'segment 210 to pivot about the pin 212 but since the outwardly extending arm 226 formed on the gear segment is normally held in fixed pivotal relation to the sideplate 32-, the gear segment 210. will pivot about the pin 228. When the gear segment 210 isso pivoted it will carry with it the pin 212iwhich, in turn, will cause the spider 2.04 to rotate about the collar 202 onthe. pinion 194. Rotation of the spider 294 as previously described will change the angular disposition of the cam 178relativeto the cam 174'.

The movement of the spider 204 accomplished: by movement of theknob 198 is greatly reduced by this means since a. full half turn of the knob 198 and the pinion'194 will'cause. thepin 212'and the spider 2494 to move onlya relatively. short distance. To aid in the position of the knob 198, theface of the spider 2% adjacent thenotches 2M may also carry suitable markings to indicate the setting of the'moistening mechanism.

As previously mentioned it is sometimes desirable to quickly move the setting of the moistening mechanism from that desired for-normal operation to the maximum setting, at'least for a. very short period of time. Provisionis made for this desirable adjustment by making the normally fixedpivot pointof the arm 226, on the gearsegment-21G, movable under certain circumstances. Asspreviously'described this pivot point is in the form of the pin- 228 carried"*by-the bracket- 230, the latter'elernent' being-married irrturrrbythearm" 232'. Ifthe position of the pin. 228 were shifted to the right as shown in Figure 5, the result would be a movement of the spider 204' comparable to a movement imparted thereto by an adjustment'ofthe knob 198 to the position of the maximum moistening. Such a shifting of the position of the pin 228'is accomplished by inflation of the bellows 242 by the operation of a suitable valve (not shown). The valve may be operated by a control member in the form of a pushbutton or the like (not shown) disposed so as to be conveniently available to the operator of the duplicating machine. As-soon as the air pressure to the bellows 242 is released, the spring 234 will operate to bring the shaft 232back' to the position substantially as-shown in Figure 5. This'spring' 234'will also normally operate to maintain the pin2'28 in afixed position since it is disposed under some compression between the bracket 236 and the Washer 244 ofthe end 246 on the arm 232.

As previously mentioned, the surface of the moisture fountain roll 16 is divided into four quadrants each having a different surface configuration. The various components' of the moistening mechanism may be designed so thatthe ductor roll 18 is in rolling contact with the fountain roll 16 no more than a quarter turn of the fountain roll, and since the relative radial disposition of the fountain roll 15 to the drive shaft 74 may be adjusted both through a selected disposition of the clutch 7i)'-on"the shaft 74, through the set screw 76, and a selected disposition of the tongue 68in the groove 72, the ductor roll-may becaused to be moved'into association with one desired quadrant of the moisture form roll.

Each of these quadrants is adapted to cause a particular pattern of moisture'to be laid down on the ductor roll 18 asitrolls in contact therewith. For example, if the moisture form roll'is so adjusted that the ductor roll 18 moves in rolling contact with quadrant a, a substantially rectangular patternof moisture may be laid down on the ductor roll, since quadrant a has a full cylindrical surface throughout its entire width as previously explained. If'on thev other hand roll 16 is so adjusted so that the ductor roll will make rolling contact with quadrant b, c or d, a pattern similar to that shown in Figure llwill be laid down on the ductor roll. This pattern will be substantially T-shaped, although the relative length of the arms of the T and the width of the base of the T will vary according to which quadrant is in rolling contact with the'ductor roll. The purpose of making available these variations in the pattern of moisture is to provide for a local adjustment of the width of the normal moisture pattern on the train of rollers associated with the moisture fountain roll so that the moisture pattern on a-master plate may be likewise varied. Provision is made for applying a greatly reduced amount of moisturetothe margins of the train of rollers and the master plate, which amount may also be varied at will.

These. possible variations are desirable since if the normal amount of.moisture is applied to the entire plate when relatively narrow sheets of stock are being utilized, excessive moisture will build up on the margins of the plate, which do not comein contact with the paper stock. ltis desirable, however, to apply a certain minimum of the moisture. to these margins of the plate since otherwise. they would become coated with. ink. when a-stock of a particular width. is to be printed, the position of'thelmoisture roll may be adjustable relative to the position'of the clutch70, as previously described, so that the quadrant most suitable for use with that width of stock will be-brought into rolling contact with the ductorroll.

Theareasb', c and d arethose which are adapted to transfer the proper amount of moisture to the marginal edges of'the'ductor'roll 18 and they are therefore relativeiy-n'arrow', as compared with-the main portions of the'qua'drants" b; c andd: The area b isactually an integral -"portion" of thequadrant a, but the" ductor roll Therefore,

will come into contact with this area d after it has rolled in contact with the main portion of the quadrant d.

As best shown in Figure 11, which is a diagrammatic representation of quadrant b, the point at which the ductor roll is brought into contact with the quadrant may be varied, as previously described, by adjustment of the control knob 198. For example, the dotted line 274 represents the point at which the ductor roll may come into contact with the quadrant b when the control knob 198 is moved to the maximum moisture position. Dotted line 276, on the other hand, represents the point at which the ductor roll 18 may come into contact with the moisture roll when the control knob 198 is in the minimum moisture position. Since the ductor roll is moved out of contact with the moisture roll at a fixed point in the cycle of operation, indicated here by the dotted line 278, the ductor r011 will be in association with the moisture roll, when the control knob 198 is adjusted as first described, for a period of time and a distance represented by the arrow 280. Similarly when the control knob 198 is adjusted for minimum moisture, the ductor roll will be in rolling contact with the moisture roll for a period of time and a distance represented by the arrow 282.

It will be seen that the point at which the ductor roll moves out of contact with the moisture roll is in the elongated area b' previously discussed. Since this point is normally fixed, adjustment of the amount of moisture being applied to the marginal edges of the plate by the area b' cannot be carried out through adjustment of the control knob 198. However, in order to accomplish an adjustment of the period of time in which the ductor roll is in association with the area b of the quadrant b, the set screw 76 shown in Figure 7 in the clutch 70 may be loosened and the relative angular positions of the roll 16 and the shaft 74 appropriately adjusted to either increase or diminish the time as desired. This adjustment in effect will cause a shifting of the dotted line 278 as indicated by the arrows 284. It should be borne in mind that this shifting of the dotted line 278 to vary the amount of moisture applied to the marginal areas is accompanied by a simultaneous and comparable shifting of the point at which the ductor roll comes into contact with the moisture roll or of the lines 274 or 276, for example. This, of course, results in a change in the amount of the moisture which is being applied to the central portion of the plate but this change may be corrected by readjusting the position of the control knob 198. I

Thus this arrangement provides for a control of the amount of moisture that is applied to the margins of a master plate in addition to the control which is exerted by the control knob 198 on the amount of moisture that is applied to the main portion of the plate. The overloading of the areas of the plate which do not come into contact with the sheets being printed is therefore avoided.

The drawings and the above discussion are not intended to represent the only possible form of this invention, in regard to details of construction. Changes in form and in the proportion of parts, as well as the substitution of equivalents, are contemplated, as circumstances may suggest or render expedient, without departing from the spirit or scope of this invention, as further defined in the following claims.

It is claimed:

1. A planographic plate dampening device comprising a moisture form roll mounted for intermittent rolling contact with a plate, a rider roll mounted for normally continuous rolling contact With said moisture form roll, a moisture fountain, a fountain roll having portions in relief spaced about the periphery thereof and being of different lengths measured axially of the roll, means for continuously rotating said fountain roll, a ductor roll mounted for swinging movement between said fountain roll and said rider roll, means for selectively adjusting said fountain roll circumferentially with respect to its drive so that a predetermined selected portion of its periphery is presented to said ductor roll during the cycle, and corn pound cam means adapted to maintain said ductor roll in rolling contact with said rider roll a fixed period in any one cycle of operation, and to maintain said ductor roll in rolling contact with said fountain roll for a selected period of time during any one cycle of operation so that said ductor roll is in rolling contact with a selected segment of said portions in relief on said fountain roll.

2. A planographic plate dampening device comprising a moisture form roll mounted for intermittent rolling contact with a plate, a rider roll mounted for normally continuous rolling contact with said moisture form roll, a moisture fountain, a fountain roll having portions in relief spaced about the periphery thereof and being of different lengths measured axially of the roll, means for continuously rotating said fountain roll, a ductor roll mounted for swinging movement between said fountain roll and said rider roll, means for selectively adjusting said fountain roll circumferentially with respect to its drive so that a predetermined selected portion of its periphery is presented to said ductor roll during the cycle, and an adjustable cam means adapted to move said ductor roll out of contact with said fountain roll and into rolling contact with said rider roll at a fixed point in the cycle of operation of said dampening device and to move said ductor roll out of such contact with said rider roll at a second fixed point in said cycle of operation, and adapted to move said ductor roll into rolling contact with said fountain roll at a selected, variable point in said cycle between said first and second points in said cycle so that said ductor roll is in rolling contact with a selected segment of said portions in relief on said fountain roll.

3. A planographic plate dampening device comprising a moisture form roll mounted for intermittent rolling contact with a plate, a rider roll mounted for normally continuous rolling contact with said moisture formroll, a moisture fountain, a fountain roll having portions in relief spaced about the periphery thereof and being of different lengths measured axially of the roll, means for continuously rotating said fountain roll, a ductor roll mounted for swinging movement between said fountain roll and said rider roll, means for selectively adjusting said fountain roll circumferentially with respect to its drive so that a predetermined selected portion of its periphery is presented to said ductor roll during the cycle, a pair of individually rotated cams normally rotating in synchronism with said fountain roll, means for varying the relative angular relation of said cams, as desired, and a control arm for said ductor roll and a pair of cam followers on said arm, each follower being disposed so as to cooperate with one of said cams, said cams having such a configuration and being so driven that they are adapted to move said followers and said control arm so that said ductor roll is moved out of contact with said fountain roll and into rolling contact with said rider roll at a fixed point in Y the cycle of operation of said dampening device, and said ductor roll is moved out of such contact with said rider roll at a second fixed point in the cycle in said cycle of operation, and said ductor roll is moved into rolling contact with said fountain roll at a selected, variable point in said cycle between said first and second points in said cycle so that said ductor roll is in rolling contact with a selected segment of said portions in relief on said fountain roll.

4. A planographic plate dampening device comprising a moisture form roll mounted for intermittent rolling contact with a plate, a rider roll mounted for normally continuous rolling contact with said moisture form roll, a moisture fountain, a fountain roll having portions in relief spaced about the periphery thereof and being of different lengths measured axially of the roll, means for continuously rotating said fountain-roll, a ductor roll mounted for swinging movement between said fountain roll and said rider roll, a cam driven in synchronism with said fountain roll, means for selectively adjusting said fountain roll circumferentially with respect to its drive' so'that'apredetermined selected portion of its periphery is'presented'to saidductor roll during the cycle, a sun gearon said cam, a second cam rotatably mounted about theaxis of rotation of'said first cam, an internal ring gear formed on saidsecond cam, a plurality of planetary gears rotatably mounted in meshing relation with said sun gear and said'internal ring gear'on a supporting member'rotatable about said axis'of rotation of said first named cam member, means for selectively adjusting the normally fixed'position of'said supporting member, a control arm for said ductorroll and a pair of cam followers on said arm; each follower being disposed so'as to cooperate with one'ofsaid cams, said cams having such a configuration and being so driven that they are adapted to move said followers and said controlarmso that said ductor roll isrnoved outofcontact with said fountain roll and into rolling contact withsaidrid'er roll at a fixed point in the cycle of operation of'said dampening'device, and said dirctorroll is'moved out of such contact with said'rider roll at "a second fixed point in the cycle in said cycle of operation, and said ductor roll is moved into rolling contact with' saidfountain roll at' a selected, variable point in saidcycle between said first and second points 'in said cycle so that said ductor roll is in'rolling contact with a selected segment of 'said'portions in relief on said'fountain roll In a duplicating'machine, the combination of an impressioncylinder adapted to carry a planographic plate,

a moisture form roll, cam means carried by said impression cylinder adapted to periodically move said moisture form roll periodically'into rolling contact'with a plate carriedby said impression cylinder, a rider roll normally inrolling contact with said moisture form roll, a moisture fountain roll having portions in relief spaced about the periphery thereof and being of'diiferent lengths measuredaxially of the roll, means for continuously rotating'said fountain roll, a ductor roll mounted to swing between said fountain roll and said rider roll, means for selectively adjusting said fountain roll circumferentially with respect to its drive so that a predetermined selected portion of its periphery is presented to said ductor roll during the cycle, and adjustable cam means rotatable with said moisture fountain roll adapted to move said ductor'roll out of contact with said moisture fountain roll and immediately into rolling contact with-said rider roll for a fixed period, to then move said ductor roll out of contact with said rider roll and to then move said ductor roll again into rolling contact with said moisture fountain roll so'that said contact is maintained for a selected period so that said ductor'roll is inrolling contact with a selected segmentof said portions in relief on said fountain roll.

6; In a duplicating machine, the combination of an impression cylinder adapted to carry a planographic plate, a moisture form roll, cam means carried by said impression cylinder adapted to periodically move said moisture form roll periodically into'rolling contact with a plate carried by said impressioncylinder, a rider roll normally in'rolling contact with said moisture form roll, a moisture fountain roll having, portions in relief spaced about theperiphery thereof and being of different lengths measured axially of the roll, means for continuously rotating said fountian roll, a ductor roll mounted to swing between' said fountain" roll andsaid rider roll, means for selectively adjusting said fountain roll circumferentially with respect'to its drive so that a predetermined selected portionof itsperiphery is presented to said ductor roll during the-cyele, a cam means adapted to maintain said ductor roll in contactwith said rider roll for a fixed period of time, a'second cam means for controlling the position of said ductor roll when out of contact with said rider roll, therelative-angular position of said second cam means to said" first named" cam means being adjustable so that theperio'dbf "time'in" whieh said ductor roll is permitted to move'into rolling' contact with said moisture fountain roll by said second cam means may be varied as desired so that said ductor roll is in rolling contact with a selected segment'of said portions in relief on said fountain roll.

7. In a duplicating'machine, the combination of an impression'cylinder adapted to carry a planographic plate, a moisture form roll having portions in relief spaced about the periphery thereof and being of dififerent lengths measured axially of the roll, cam means'carried by said impression cylinderadapted to periodically move said moistureiform roll periodically into rolling contact with aplate carried by said impression cylinder, a rider roll normally in rolling .contact with said moisture form roll, a moisture 'fountaiuroll, means for :continuously rotating said fountain 'roll, a ductor roll mounted to swingrbetween said fountain'roll and'saidriderrroll, means for selectively adjusting said fountain'roll circumferentially with respect to its drive so that a predetermined selected portion of its periphery is presented to said ductor roll during the cycle, a canrmeansmounted'to rotate with'said moisture fountain roll, a second cam means coxi'ally and rotatably mounted on said firstnamed cam means, a sun gear mounted to rotate coaxially with said first named cam means, an internal ringgear formed on said secondcam means, a spider member 'rotatably mounted on an extension of the moisture fountain roll shaft, a plurality of planetary gears carried'by said spider in meshing relation with said sun'gear and said internal ring gear on said second named'cam means, and means for adjusting the relative'angularrelation between said first and second named cam means so that said ductor roll is in rolling contact with a'select' segment of said'portions in relief on said fountain roll.

8. In a printing press fountain mechanism, the combination of a fountain, a fountain roll having its periphery divided into quadrants, said quadrants having portions 'in relief of different configurations, means for continuously rotating said fountain roll, a third roll, a ductor roll mounted for swinging movement between said fountain roll and said third roll, means for selectively adjusting said fountain roll circumferentially with respect to its drive to present a selected quadrant of its periphery to said ductorroll during the cycle, compound means for moving said' ductor roll in rolling contact with said third roll in a fixed period in any one cycle of operation, and for moving said ductor roll in rolling contact with said fountain roll for a selected period of time during any one cycle of operation, and means for regulating said compound cam' means to adjust'the rolling contact of said ductor-roll on'said selected quadrant of said fountain roll.

9. In a-printing press fountain mechanism, the combination of afountain, a fountain roll having its periphery divided into segments, said segments having portions in relief of different'configurations, means for rotating said fountain roll, a third roll, a ductor roll mounted for movement between said fountain roll and said third roll, means for selectively adjusting said fountain roll circumferentially with respect to its drive to present a selected segment of its periphery to said ductor roll during the cycle, cam means for moving said ductor roll in rolling contact with said third roll for a predetermined period in any one cycle of operation, and for moving said ductor roll in rolling contact with said fountain roll'for a selected period of time during any one cycle of operation, and meansfor overriding said cam means so as to cause said ductor roll to move into contact with said fountain roll immediately after it is moved out of rolling contact with said third roll.

10. In a printing press fountainmechanism, the combination of a fountain, a fountain roll'having itsperiphery divided intosegments, said segments-having porti'ons'inrelief'ofdiflerent configurations, means for-"rotatingsaidfountain'roll, a'thirdr'oll, a'ductor roll mount ed for movement between said fountain roll and said third roll, means for selectively adjusting said fountain roll circumferentially With respect to its drive to present a selected segment of its periphery to said ductor roll during the cycle, and means for moving said ductor roll in rolling contact with said third roll for a predetermined period in any one cycle of operation, and for moving said ductor roll in rolling contact With said fountain roll for a selected period of time during any one cycle of operation.

11. In a printing press fountain mechanism, the combination of a fountain, a fountain roll having T-shaped portions in relief spaced about the periphery thereof, means for continuously rotating said fountain roll, a third roll, a ductor roll mounted for swinging movement between said fountain roll and said third roll, means for selectively adjusting the fountain roll circumferentially with respect to its drive so that a predetermined selected portion of its periphery is presented to said ductor roll during the cycle, cam means for moving said ductor roll in rolling contact with said third roll a fixed period in any one cycle of operation, and for moving said ductor roll in rolling contact with said fountain roll for a selected period of time during any one cycle of operation, and means for adjusting said cam means to vary the period of time said ductor roll is in contact With said fountain roll.

References Cited in the file of this patent UNITED STATES PATENTS 1,210,559 Story Jan. 2, 1917 1,683,243 Blaine Sept. 4, 1928 2,177,253 Hal-less Oct. 24, 1939 2,354,981 Barber Aug. 1, 1944 2,374,668 Davidson May 1, 1945 FOREIGN PATENTS 415,124 Great Britain Mar. 19, 1934 

